Tennis-racket.



O. A. JOHNSON.

TENNIS RACKET. APPLICATION FILED SEPT. 25, 1915.

Pz ztented June 27, 1916.

I n venfo 7 OLE A. JOHNSON, OF CLEVELAND, OHIO. a

TENNIS-RACKET.

Specification of Letters Patent.

Application filed September 25, 1915. Serial No. 2,597.

I T 0 all whom it may concern Be it known that I, OLE A. JOHNSON, acitizen of theUnited States, residing at Cleveland, in the county ofCuyahoga and State of Ohio, have invented a certain new and usefulImprovement in Tennis-Rackets, of which the following is a full, clear,and exact description;

This invention relates to animproi'ement in tennis rackets, the objectofthe invention being to provide a stringing of the racket wherebystrength is imparted to the net of strings and at the same time providesa means for preventing side slipping or sidewis displacement of thestrings,more particularly those strings adjacent the center of theracket where the hardest usage comes.

Generally speaking, the invention comprises the elements andcombinations thereof set forth in the accompanying claims.

Reference should be had to the accom panying drawings forming a part ofthis specification in which Figure 1 is an elevation of aracketembodying a stringing according to my invention; Fig. 2 is an elevationof a portion of the stringing of the racket showing in more detail theembodiment of my invention.

In tennis rackets, as usually constructed, z. 6., with an oval orsubstantially oval head, the center of percussion of the head, or, inother'words, that portion of the racket which when brought into contactwith a ball gives the greatest effective impulse to the ball, is an areasubstantially at the central portion of the strings of the racket. Everyexperienced tennis player seeks to impactthe ball at the center of thenet of the racket,

and this is true not only of direct drives but of all those strokeswhich involve cutting the ball. The strokes which involve what is termedcutting the ball or imparting a ro-,

tating movement as well as a projectile movement to the ball, dependupon the fact that the strings engage with the furry cover of" ball, andmakes results uncertain and undependable.

Various means have been proposed forpreventing slipping of the strings,but so far as I am aware, the particular method which I employ foraccomplishing this resuit is new;

I employ the usual longitudinal strings 1 and the usual transversestrings 2, and in addition to these strings I employ four strlngs whichare numbered respectively 3, 4, 5 and 6. The strings 3 and & extend in adiagonal direction across the head of the racket and are parallel toeach other. Like wise the strings 5 and 6 extend in a diagonal directionacross the racket and are parallel with each other. The strings 5 and 6extend at an angle with respect to the strings 3 and 4 and at theirpoint of intersection inclose a diamond-shaped area which I haveindicated by the reference numeral 7. The strings 3, 4, 5 and 6 are soplaced with respect to the usual strings of the racket that the space 7inclosed is at substantially the center of the racket and comprehendsthat space upon the strings of the racketlwhich is the area of mosteffective engagement with the ball,

Patented June 27, i916.

sometimes called the center of percussion of the racket.

The invention may be practised in two ways,either by making the strings3, 4, 5 v

and 6 a continuation of the stringing of the racket or the strings maybe put in sepastringing. For instance,.this string may be fastened bymeans of a knot at 8 extended through suitable openings in the racket,as indicated by dotted lines at 9; thence extended through the racket asindicated at 10; thence extended through and along the outer edge of theracket as indicated in dotted lines :at 11 thence extended-through andalong the outer edge of the racket as indicated at 12; thence extendedthrough the racket as indicated by dotted lines at-13 and tied in a knotas indicated at 14'.

Inmakingthe reinforcedstringing as a part of the regular stringing ofthe racket I would preferably make this reinforced stringing as acontinuation of the transverse strings 2. Itwill be understood that allof i the transverse strings on the racket are made of one lon string ofgut. This string is usually 19 eet long and it requires less than 19feet to provide the transverse strings ofthe racket. \Vhat is left overof the string could readily be utilized in producing the reinforcedstringing without severing the gut.

The continuous stringing of the racket does not produce any betterresults than where a separate string is used, but is, perhaps, a littlecheaper in the manufacturing cost where the racket is being strungoriginally and restrung than putting in the reinforcing strings as anextra stringing. Of course, the reinforced stringing may readily beapplied to a racket already strung, and will produce the desired effect.

There is another advantage incident to-the arrangement of the reinforcedstrings, and that is the fact that the strings in defining the areawhich is the center of percussion of the racket, enable the player tomore readily distinguish this area as he is applying his racket to theball. This is particularly true when the strings 3 and 4 and 5 and 6 aremade of a gut having a color different than the color of the gut formingthe main stringing of the racket. This is quite an advantage for reasonswhich will be obvious.

Having described my invention, I claim:

1. In a tennis racket, the combination with a suitable frame, transverseand longit1'1di nal strings secured in the frame of the racket andstrings extending diagonally across the frame of the racket, saidstrings inclosing an area including only a portion of said transverseand longitudinal strings, which comprehends the center percussion of theracket.

2. A tennis racket, comprising a frame, strings extending longitudinallyand transversely thereof and woven to; form a net, other stringsextending across the head of the racket extending diagonally withrespect to the first mentioned strings of the racket, the said otherstrings being woven into the net and inclosing a portion of the netincluding only the said longitudinally and transversely extendingstrings, which is at the center of percussion of the racket.

3. A tennis racket, comprising a head having a net work oflongitudinally and transversely extending strings, two pairs of parallelstrings extending across the said netting, said pair of stringsextending at an angle to each other and to the strings of the with eachother and inclosing a space which includes only a portion of thelongitudinally and transversely extending strings, which space includesthe center of percussion of the racket.

5. A. tennis racket, comprising a frame having a net of. longitudinallyand transversely extending strings, a single string tied at one point tothe frame of the racket extending diagonally across the racket, thenceextending along an outer edge of the racket, thence extending across thenet of the racket -parallel to the direction of the first mentionedstring, thence extending along an outer edge of the racket, thenceextending transversely of the netting of the racket, thence extendingupon an outer portion of the racket, thence extending across the net ofthe racket parallel to the, last mentioned string and then tied to theracket.

In testimony whereof, I hereunto afiix my signature.

OLE A. JOHNSON, F mmerly 02a A. J. Th'orby'omtsen.

Gupta 0! this potent my be obtained for are cent: each, by addressingthe "commissioner of 2mm,

Washington, D. 0." t

